NEW YORK (Reuters Health) – Adults with eosinophilic esophagitis (EoE) may not get much benefit from eliminating food antigens from their diet based on skin testing, according to a new study.
Researchers found that only four out of 15 patients achieved complete remission on a directed elimination diet, according to a study online August 6 in the Journal of Allergy and Clinical Immunology
“The results of our study question the validity of skin testing to address food allergy in adult EoE,” lead author Dr. Javier Molina-Infante, at the Hospital San Pedro de Alcantara in Caceres, Spain, told Reuters Health by email.
Each of the 15 patients, all of whom were taking high-dose omeprazole, underwent three types of skin tests measuring their reaction to 26 foods. The tests were skin prick, prick-prick, and atopy patch tests. Prick-prick tests had the highest rate of food allergy detection and atopy patch tests performed the worst, the researchers found.
The researchers used the results to design individual six-week diets for the patients. Food items were removed if they elicited a positive result in at least one test.
The disease was considered resolved if the symptoms had disappeared and histologic analysis showed less than 5 eosinophils/high-powered field. Patients with symptoms and greater than 15 eosinophils/high-powered field after dietary modification were considered non-responders.
Dr. Molina-Infante and his colleagues had originally enrolled 22 patients, but five opted out because of the difficulty of the diet and two did not show skin test responses to any foods, even after multiple tests.
In addition to the four responders (27%), one patient achieved clinical remission but only partial histologic response.
The problem with designing diets based on skin testing appears to be the limited sensitivity of the tests, the researchers write. Dr. Molina-Infante said a six-food elimination diet may be more effective. In this diet, the foods are reintroduced one by one, testing the results endoscopically. It is a lengthier and more costly process, the researchers write, but may be more effective.
The “empirical six-food elimination diet has lately shown a 70% efficacy in adults, with the advantage of identifying food triggers by reintroducing all the avoided food groups,” Dr. Molina-Infante said.
A separate study published in March in Gastroenterology found that as many as 94% of adult patients saw their symptoms improve while on the six-food elimination diet.
“Based on the available data, I agree with the authors’ conclusion that the empiric elimination diet is a superior approach compared with the allergy-testing-directed diets in adults with EoE,” said Dr. Ikuo Hirano of Northwestern University School of Medicine in Chicago, who worked on the study in Gastroenterology.
Dr. Molina-Infante also suggested simply removing cow milk from the patient’s diet, which has led to a 65% remission rate in children. And topical steroids may treat the condition if dietary therapy does not work or patients are unwilling to try it.
J Allergy Clin Immunol 2012.